Xpbesekvajxonofglycebideoils



?atented May i942 stares r greater 2,282,05t- L rassaava'rron or streams oms Kenneth C. D. Hickman and James G. Baxter,

7 Rochester, N. Y.,

ucts Inc., Delaware No Drawing.

assignors to Distillation Prod- Rochcster, N. Y.,

a corporation of Application October 5, 1938, Serial No. 233,496

3 Claims. ((31.260-3985) The manner in which the oxidation takes placeand methods for protecting against oxidation have been actively investigated, but the problem The oxidation results in the known and can be selected from any up-to-date text book on organic chemistry. Where the suitability of a particular material is in question its action can be determined by means of a simple experimental test. Examples of suitable materials are alkali bicarbonates and alkali sulfites such as sodium bicarbonate, sodium sulfite or calcium sulfite and mixtures thereof; neutral hydrosulfites such as potassium hydro-sulfite; alkali phosphites hypophosphites ferrous, cerous, manganous, titanous, stannous and chromous salts such as ferrous chloride and 'cerous sulfate; hydroquinone, and salts and other has not been previously solved. The protection of vitamin containing oils is of particular importance because these expensive substances are.

destroyed simultaneously with the oil.-

This invention has for its object to provide "an improved method for protecting glyceride oils, fractions thereof, and/or substances-derived therefrom against oxidation. A further object is to provide an improved method for protecting vitamin containing oils, against oxidation. A further object is to provide a method whereby the peroxide content of natural glyceride oils and the like is prevented from exerting its harmful action. A still further object is'to. provide a method for protecting glyceride oils'against oxidation, by means other than the addition of anti-oxidants to the oil itself. Other objects will become apparent as the description of the invention proceeds.

We have discovered that peroxides contained in natural glyceride oils can be directly removed from the oil substantially as fast as formed by disposing or storing it in contact with a'layer of water which is immiscible with the oil and which contains a substance capable of reacting with and destroying the peroxide content of the oil. Peroxldes in the oil pass or diffuse into contact with the immiscible layer where they are effectively captured and prevented from exerting harmful action. that as long as the peroxides are efiectively removed from the oil the rest of the oxygen which remains dissolved in the oil will exhibit little or no harmful action. Since this procedure. does not involve the direct addition of an anti-oxidant to the oil and dispersion of such materials throughout the oil, problems of removing such substances or subsequent purification of the oil are avoided.

Substances which react'with peroxides are well We have further discovered derivatives of' hydrazine, hydroxylamine, aromatic'phenols and amines.

' In the case of the highly reactive reducing agents such as hydrazine, hydroxylamine, the phenols, hydrcquinone and aromatic amines the immiscible layer or solution can contain rather minute quantities such as up to one tenth of one percent. They may be prevented from passing into the oil phase, if there is such a tendency, by the addition of alkali and/or alkaline sulfites. The other peroxide destroying substances listed above usually should be employed in'somewhat higher'proportions such as one to 20 percent based on the amount of immiscible solvent. Saturated solutions of these materials are quite successful. These proportions are not critical and can be varied substantially. v

The invention may be employed to protect glyceride oils and fats or fractions thereof which are subject to destruction due to oxldative influences. Examplesof such substances are codliver, halibut liver, menhaden, tuna liver, etc. fish oils; soy-bean, cottonseed, olive, linseed, etc. oils.

Examples of fats which may be protected are butter, lard, and hydrogenated oils. Our invention is of particular advantage for protecting vitamin containing oils and fractions thereof, such as the fractions obtained by high vacuum distillation of such oils, which fractions contain Example 10 cc. of vitamin A concentrate prepared from pollack oil by distillation at a pressure of approximately .001 mm. in a high vacuum, short path still was added to a cylindrical glass vessel approximately 1 in diameter. To a similar Assay Assay Assay Ass y Composmon days 7 days 13 days 17 days Pollack concentrate 41,000 30, 700 12,700 3,700 Pollack concentrate with percent aqueous sodium sulphite.. 41,000 39,800 29,800 8, 540

It is apparent from the data that a substantial protection was afforded the vitamin content of the oil by the immiscible aqueous sodium sulphite layer upon which the vitamin containing oil was floated. Since the test conditions were much more drastic than normal storage conditions, the protection afforded by the invention would be much greater under ordinary conditions. I

What we claim as new and desire to be secured by Letters Patent of the United States is:

l. The process of protecting a glyceride oil which contains vitamin A against oxidation without actual admixture of a protecting agent therewith whereby the vitamin A and the glyceride oil can be stored without substantial deterioration and can be separated with ease from the protect- 1 tion ing agent, which process comprises in combination floating a body of the glycericle oil of substantial bulk during the period of protection upon an aqueous body immiscible with the oil in which aqueous body is dissolved a substance capable of reacting with peroxides.

2. The process of protecting a glyceride oil against oxidation without actual admixture of a protecting agent therewith whereby the glyceride oil can be stored without substantial deterioration and can be separated with ease from the protecting agent, which process comprises in combination floating a body of the glyceride oil of substantial bulk during the period of protection upon an aqueous body immiscible with the oil in which aqueous body is dissolved a substance capable of reacting with peroxides.

3. The process of protecting a glyceride oil which contains vitamin A against oxidation without actual admixture oi! a protecting agent therewith whereby the'vitamin A and the glyceride oil can be stored without substantial deterioration and can be separated with ease from the protecting agent, which process comprises in combination floating a body of the glyceride oil of substantial bulk during the period of protecupon an aqueous body immiscible with the oil in which aqueous body is dissolved sodium sulphite.

*KENNETH C. D. HICKMAN. JAMES G. BAX'I'ER. 

